Modal Analysis and Optimization of Electric Vehicle Chassis Structure

Abstract

The interior noise of electric vehicles (EVs) at low velocities is predominantly attributed to structural vibrations. This study proposes a systematic optimization of the EV chassis structure through modal analysis, integrated with spectral characteristics of interior noise. Initially, finite element models of critical chassis components were developed and validated via experimental modal testing. Subsequent the modal frequency and vibration mode of each component were obtained by finite element analysis. By correlating the frequency spectrum of interior noise with the chassis modal frequencies, the rear subframe and strengthening plates were identified as priority optimization targets. Targeted structural reinforcements were implemented to elevate the natural frequencies of these components, thereby achieving effective frequency avoidance and mitigating structural vibrations. The proposed methodology demonstrates a data-driven approach to enhance NVH (Noise, Vibration, and Harshness) performance of the vehicle.